package com.glela.goods.utils;

import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

public class AESUtils {
	/** 加密密码 */
	private static final String password = "http://xzhuang.com/";
	
	/**
	* **********************************************
	* @Title: encrypt 
	* @Description: 加密
	* @param @param content 需要加密的内容
	* @param @return 
	* @return byte[]
	* @throws	
	* @author NingChongQing	
	* @date 2018年3月16日 下午3:30:06 
	* **********************************************
	 */
	public static String encrypt(String content) {
		try {
			KeyGenerator kgen = KeyGenerator.getInstance("AES");
			kgen.init(128, new SecureRandom(password.getBytes()));
			SecretKey secretKey = kgen.generateKey();
			byte[] enCodeFormat = secretKey.getEncoded();
			SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
			// 创建密码器
			Cipher cipher = Cipher.getInstance("AES");
			byte[] byteContent = content.getBytes("utf-8");
			// 初始化
			cipher.init(Cipher.ENCRYPT_MODE, key);
			// 加密
			byte[] encryptBytes = cipher.doFinal(byteContent);
			return parseByte2HexStr(encryptBytes);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}

	/**
	* **********************************************
	* @Title: decrypt 
	* @Description: 解密
	* @param @param content 待解密内容
	* @param @param password
	* @param @return 
	* @return byte[]
	* @throws	
	* @author NingChongQing	
	* @date 2018年3月16日 下午3:30:44 
	* **********************************************
	 */
	public static String decrypt(String content) {
		try {
			byte[] contentBytes = parseHexStr2Byte(content);
			KeyGenerator kgen = KeyGenerator.getInstance("AES");
			kgen.init(128, new SecureRandom(password.getBytes()));
			SecretKey secretKey = kgen.generateKey();
			byte[] enCodeFormat = secretKey.getEncoded();
			SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
			// 创建密码器
			Cipher cipher = Cipher.getInstance("AES");
			// 初始化
			cipher.init(Cipher.DECRYPT_MODE, key);
			// 解密
			byte[] decryptBytes = cipher.doFinal(contentBytes);
			return new String(decryptBytes); 
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}

	/**
	* **********************************************
	* @Title: parseByte2HexStr 
	* @Description: 将二进制转换成16进制
	* @param @param buf
	* @param @return 
	* @return String
	* @throws	
	* @author NingChongQing	
	* @date 2018年3月16日 下午3:31:04 
	* **********************************************
	 */
	public static String parseByte2HexStr(byte buf[]) {
		StringBuffer sb = new StringBuffer();
		for (int i = 0; i < buf.length; i++) {
			String hex = Integer.toHexString(buf[i] & 0xFF);
			if (hex.length() == 1) {
				hex = '0' + hex;
			}
			sb.append(hex.toUpperCase());
		}
		return sb.toString();
	}

	/**
	* **********************************************
	* @Title: parseHexStr2Byte 
	* @Description: 将16进制转换为二进制
	* @param @param hexStr
	* @param @return 
	* @return byte[]
	* @throws	
	* @author NingChongQing	
	* @date 2018年3月16日 下午3:31:14 
	* **********************************************
	 */
	public static byte[] parseHexStr2Byte(String hexStr) {
		if (hexStr.length() < 1)
			return null;
		byte[] result = new byte[hexStr.length() / 2];
		for (int i = 0; i < hexStr.length() / 2; i++) {
			int high = Integer.parseInt(hexStr.substring(i * 2, i * 2 + 1), 16);
			int low = Integer.parseInt(hexStr.substring(i * 2 + 1, i * 2 + 2), 16);
			result[i] = (byte) (high * 16 + low);
		}
		return result;
	}

	public static void main(String args[]) throws Exception {
		String content = "113";
		System.out.println("加密前：" + content);
		String encryptResultStr = encrypt(content);
		System.out.println("加密后：" + encryptResultStr);
		String decryptResult = decrypt(encryptResultStr);
		System.out.println("解密后：" + new String(decryptResult));
	}
}
